<template>
  <div class="shopcart">
    <div class="content" @click="toggleList">
      <div class="content-left">
        <div class="logo-wrapper">
          <div class="logo"  :class="{'highlight':totalCount>0}">
            <i class="icon-shopping_cart"  :class="{'highlight':totalCount>0}"></i>
          </div>
          <div class="num" v-show="totalCount>0">{{totalCount}}</div>
        </div>
        <div class="price" :class="{'highlight':totalPrice>0}">￥{{totalPrice}}</div>
        <div class="desc">另需配送费￥{{deliveryPrice}}元</div>
      </div>
      <div class="content-right" @click.stop.prevent="pay">
        <div class="pay" :class="payClass">
          {{payDesc}}
        </div>
      </div>
    </div>
    <div class="ball-container">
      <div class="ball" transition="drop" v-for="ball in balls" v-show="ball.show">
        <div class="inner inner-hook"></div>
      </div>
    </div>
    <div class="shopcart-list" v-show="listShow" transition="fold">
      <div class="list-header">
        <h1 class="title">购物车</h1>
        <span class="empty" @click="empty">清空</span>
      </div>
      <div class="list-content" v-el:list-content>
        <ul>
          <li class="food" v-for="food in selectFoods">
            <span class="name">{{food.name}}</span>
            <div class="price">
              <span>￥{{food.price * food.count}}</span>
            </div>
            <div class="cartcontrol-wrapper">
              <cartcontrol :food="food"></cartcontrol>
            </div>
          </li>
        </ul>
      </div>
    </div>
  </div>
  <div class="list-mask" transition="fade" v-show="listShow" @click="hideList"></div>
</template>
<script>
import cartcontrol from '../cartcontrol/cartcontrol'
import BScroll from 'better-scroll'
export default {
  props: {
    selectFoods: {
      type: Array
    },
    deliveryPrice: {
      type: Number,
      default: 0
    },
    minPrice: {
      type: Number,
      default: 0
    }
  },
  data () {
    return {
      balls: [
        {show: false},
        {show: false},
        {show: false},
        {show: false},
        {show: false}
      ],
      dropBalls: [],
      fold: true
    }
  },
  computed: {
    totalPrice () {
      let total = 0
      this.selectFoods.forEach((food) => {
        total += food.price * food.count
      })
      return total
    },
    totalCount () { // 所选的商品的总和，通过这个来让购物车logo变化和 把多少元配送变成还差多少元配送
      let count = 0
      this.selectFoods.forEach((food) => {
        count += food.count
      })
      return count
    },
    payDesc () {
      if (this.totalPrice === 0) {
        return `￥${this.minPrice}起送`
      } else if (this.totalPrice < this.minPrice) {
        let diff = this.minPrice - this.totalPrice
        return `还差￥${diff}起送`
      } else {
        return '去结算'
      }
    },
    payClass () {
      if (this.minPrice < this.totalPrice) {
        return 'enough'
      } else {
        return 'not-enough'
      }
    },
    listShow () {
      if (!this.totalCount) {
        this.fold = true
        return false
      }
      let show = !this.fold
      if (show) {
        this.$nextTick(() => {
          if (!this.scroll) {
            this.scroll = new BScroll(this.$els.listContent, {
              click: true
            })
          } else {
            this.scroll.refresh()
          }
        })
      }
      return show
    }
  },
  methods: {
    pay () {
      if (this.totalPrice < this.minPrice) {
        return
      }
      window.alert(`请支付${this.totalPrice}元`)
    },
    hideList () {
      this.fold = true
    },
    empty () {
      this.selectFoods.forEach((food) => {
        food.count = 0
      })
    },
    drop (el) {
      for (let i = 0; i < this.balls.length; i++) {
        let ball = this.balls[i]
        if (!ball.show) {
          ball.show = true
          ball.el = el
          this.dropBalls.push(ball)
          return
        }
      }
    },
    toggleList () {
      if (!this.totalCount) {
        return
      }
      this.fold = !this.fold
    }
  },
  transitions: {
    drop: {
      beforeEnter (el) {
        let count = this.balls.length
        while (count--) {
          let ball = this.balls[count]
          if (ball.show) {
            let rect = ball.el.getBoundingClientRect()
            let x = rect.left - 32
            let y = -(window.innerHeight - rect.top - 22)
            el.style.display = ''
            el.style.webkitTransform = `translate3d(0, ${y}px, 0)`
            el.style.transform = `translate3d(0, ${y}px, 0)`
            let inner = el.getElementsByClassName('inner-hook')[0]
            inner.style.webkitTransform = `translate3d(${x}px, 0, 0)`
            inner.style.transform = `translate3d(${x}px, 0, 0)`
          }
        }
      },
      enter (el) {
        /* eslint-disable no-unused-vars */
        let rf = el.offsetHeight
        this.$nextTick(() => {
          el.style.webkitTransform = 'translate3d(0, 0, 0)'
          el.style.transform = 'translate3d(0, 0, 0)'
          let inner = el.getElementsByClassName('inner-hook')[0]
          inner.style.webkitTransform = 'translate3d(0, 0, 0)'
          inner.style.transform = 'translate3d(0, 0, 0)'
        })
      },
      afterEnter (el) {
        let ball = this.dropBalls.shift()
        if (ball) {
          ball.show = false
          el.style.display = 'none'
        }
      }

    }
  },
  components: {
    cartcontrol
  }
}
</script>
<style lang="stylus" rel="stylesheet/stylus">
@import '../../common/styls/mixin';
  .shopcart
    position fixed
    left 0
    bottom 0
    z-index 50
    width 100%
    height 48px
    .content
      display flex
      background #141d27
      .content-left
        flex 1
        font-size 0
        .logo-wrapper
          display inline-block
          vertical-align top
          position relative
          top -10px
          margin 0 12px
          padding 6px
          width 56px
          height 56px
          box-sizing border-box
          border-radius 50%
          background #141d27
          .logo 
            width 100%
            height 100%
            border-radius 50%
            background #2b343c
            text-align center
            &.highlight
              background rgb(0, 160, 220)
            .icon-shopping_cart
              font-size 24px
              color #80858a
              line-height 44px
              &.highlight
                color #fff
          .num
            position absolute
            top 0
            right 0
            width 24px 
            height 16px
            line-height 16px
            text-align center
            border-radius 16px
            font-size 9px
            font-weight 700
            color #fff
            background rgb(240, 20, 20)
            box-shadow 0 4px 8px 0 rgba(0, 0, 0, .4)
        .price
          display inline-block
          vertical-align top
          color rgba(255, 255, 255, .4)
          font-size 16px
          font-weight 700
          line-height 24px
          margin-top 12px
          padding-right 12px
          box-sizing border-box
          border-right 1px solid rgba(255, 255, 255, .1)
          &.highlight
            color #fff
        .desc
          display inline-block
          vertical-align top
          line-height 24px
          margin 12px 0 0 12px
          color rgba(255, 255, 255, .4)
          font-size 16px
          font-weight 700
      .content-right
        flex 0 0 105px
        width 105px
        .pay 
          height 48px
          line-height 48px 
          text-align center
          font-size 12px 
          font-weight 700
          color rgba(255, 255, 255, .4)
          background #2b333b
          &.not-enough
            background #2b333b
          &.enough
            background #00b43c
            color #fff
    .ball-container
      .ball
        position fixed
        left 32px
        bottom 22px
        z-index 200
        &.drop-transition
          transition all 0.4s cubic-bezier(0.49, -0.29, 0.75, 0.41)
          .inner
            width 16px
            height 16px
            border-radius 50%
            background rgb(0, 160, 220)
            transition all 0.4s linear
    .shopcart-list
      position absolute
      top 0
      left 0
      z-index -1
      width 100%
      &.fold-transition
        transition all .5s 
        transform translate3d(0, -100%, 0)
      &.fold-enter, &.fold-leave
         transform translate3d(0, 0, 0)
      .list-header
        height 40px
        line-height 40px
        padding 0 18px
        background #f3f5f7
        border-bottom 1px solid rgba(7, 17, 27, 0.1)
        .title
          float left
          font-size 14px 
          color rgb(7, 17, 27)
        .empty
          float right
          font-size 12px
          color rgb(0, 160, 220)
      .list-content
        padding 0 18px
        max-height 217px
        overflow hidden
        background #fff
        .food 
          position relative
          padding 12px 0
          box-sizing border-box
          border-1px(rgba(7, 17, 27, 0.1))
          .name
            line-height 24px 
            font-size 14px
            color rgb(7, 17, 27)
          .price
            position absolute
            right 90px
            bottom 12px 
            line-height 24px
            font-size 14px
            font-weight bold
            color rgb(240, 20, 20)
          .cartcontrol-wrapper
            position absolute
            right 0
            bottom 6px
  .list-mask
    position fixed
    top 0
    left  0
    bottom  0
    right 0
    z-index 40
    width 100%
    height  100%
    -webkit-backdrop-filter blur(10px)
    backdrop-filter blur(10px)
    &.fade-transition
      transition all 0.5
      opacity 1
      background rgba(7, 17, 27, .6)
     &.fade-enter, &.fade-leave
      opacity 0
      background rgba(7, 17, 27, 0)
        
</style>